After years of litigation and multiple appeals, Tyler and Cameron Winklevoss have decided to take their cash and end their judicial crusade against Facebook and Mark Zuckerberg.

The twins, who became mainstream figures thanks to the success of The Social Network, accused Zuckerberg of stealing the idea and technology for Facebook when they were classmates at Harvard. The two sides settled in 2008 in a deal worth approximately $200 million today, but in the last year the twins have tried to appeal the settlement based on the claim Facebook and Zuckerberg defrauded them on the true value of Facebook stock.

The twins lost in an appeal at the Ninth Circuit Court of Appeals, with the court declaring that, “at some point, litigation must come to an end. That point has now been reached.” The Winkelvii didn’t agree though, and they appealed their case to the U.S. Supreme Court.

Now, after “careful consideration,” the twins have decided to withdraw their appeal, according to Reuters.

We’re not surprised: the U.S. Supreme Court was extremely unlikely to even take their case, much less rule in their favor. We doubt this will be the last time we hear from the twins, though.

Despite recent legal defeats, Tyler and Cameron Winklevoss have decided to take their feud with Facebook and Mark Zuckerberg all the way to the Supreme Court.

The twins, made into household names thanks to The Social Network, have been trying hard to rescind the settlement from their lawsuit against Mark Zuckerberg in 2004. The two sides settled in 2008 in a deal worth approximately $200 million today, but have since had a change of heart. In dispute is the market value of Facebook’s stock when the two sides settled, an issue that could quadruple the amount of the settlement.

In December 2010 though, the Ninth Circuit Court of Appeals ruled that the settlement would stand. “For whatever reason, they [the Winklevosses] now want to back out. Like the district court, we see no basis for allowing them to do so,” Chief Justice Alex Kozinski wrote at the time. “At some point, litigation must come to an end. That point has now been reached.”

Apparently the Winklevoss twins don’t agree. On Monday, their law firm released a statement announcing that they would appeal the Ninth Circuit’s ruling. “The law firm of Howard Rice announced that its clients, Cameron and Tyler Winklevoss and Divya Narendra, intend to file a Petition for Certiorari with the United States Supreme Court in the ongoing dispute with Facebook and Mark Zuckerberg,” law firm Howard Rice announced.

Howard Rice contends that the Winklevii were defrauded by Facebook and Zuckerberg and that Facebook committed securities fraud during the mediation that resulted in the 2008 settlement. Neither the district court nor the Ninth Circuit have sympathized with the twins, making it unlikely that the Supreme Court will even hear the case. The Supreme Court takes less than five percent of cases and generally only takes cases where constitutional issues are at stake.

Tyler and Cameron Winklevoss, the twins that already launched one lawsuit against Facebook, claiming that Mark Zuckerberg stole their idea for a social network, are now suing Facebook and Mark Zuckerberg again.

Even though the first lawsuit ended with a 65-million-dollar settlement, the Winklevosses now claim that Zuckerberg lied to them about the value of Facebook and is guilty of securities fraud, demanding an unspecified amount of (extra) money.

Facebook has filed new legal papers in answer to the suit, claiming the Winklevosses are suffering from “settler’s remorse,” and that they had calculated the value of Facebook themselves, based on a truthful press release from a couple of months earlier. Facebook claims that Mark Zuckerberg wasn’t obligated to inform them of the true value of the company.

From Facebook’s new legal papers: “Their fraud claim is based on omission: they fault Facebook for not volunteering a more recent – and, they claim, lower – valuation of different Facebook stock. They insist that their sworn enemy had some special duty to open its books and volunteer any information that bears on the value of this closely held company.”

The story of the first lawsuit was widely popularized through David Fincher’s movie The Social Network. The Winklevoss twins originally hired Zuckerberg to create a college-based social network for them, and Zuckerberg agreed but eventually abandoned that project to build a rival service, which would end up being Facebook. The 65 million that the Winklevosses originally settled for is a hefty sum, but who knows, perhaps they end up getting even more from Facebook.